Valve.



'0. cockauam n. M-ACNICOLL.

. VALVE.

APPLICATION FILED MAY I6. I918.

Patented Apr. 1, 1919.

David Coclwr Dana/c/ Mac y 4% m y s'rnrns PATENT onnion;

DAVID GOGKIBURLN' AND DONALD MAcNICOIiL, OF'GARDONALD, NEAR GLASGOW,

SCOTLAND, ASSIGNORS T0 COCKLBURNS LIMITED, OF: CARDONALD, NEAR GLAS- GOW, SCOTLAND.

VALVE.

Specification of Letters Patent.

Patented Apr. 1, 1919.

Application filed May 16, 1918. Serial No. 234,949.

To all whom it may concern:

Be it known that we, DAVID CooKBURN and DONALD MAoNIooLL, both subjects of the King of the United Kingdom of Great Britain and Ireland, and residing at ,Cardonald, near Glasgow, Scotland, have invented a certain new and useful Improvement in Valves, of which the following is a specification.

This invention relates to improvements in double beat valves of the balanced type fitted with a flexible diaphragm imprisoned within a cell, said diaphragm being deflected when the valve is seated sufliciently to accommodate the difference in expansion between the valve faces and the seat faces.

The invention has for its primary object to counteract tendency to upset the balance of the valve by pressure of fluid which has passed to the farther side of the valve seat and urges the valve in the direction away from its seat, to which end provision is made for admission of such fluid to the diaphragm cell at the back of the diaphragm so as to neutralize the effort which has otherwise to be overcome in reseating the valve.

Another object is to render practicable the simultaneous grinding of the valve faces of both beats.

The figure of the accompanying drawing is a vertical section of one form of double beat valve embodying the present improvement.

As shown, there is fitted to the beat which is held on its seat by the fluid pressure a thin flexible metallic diaphragm 1 imprisoned in a cell between the valve element 2 and a covering member 3 secured to said valve element 2 and loosely surrounding the valve spindle 5. The diaphragm is engaged near its center between a collar 5 on the valve spindle 5 and a backing member 9 threaded on the spindle, while its peripheral edge is engaged between the covering member 3 and an internal ledge on the valve element 2. A small opening 3 in the covering element 3 aflords access for steam to the upper side of the diaphragm. The arrangement shown permits limited movement in the cell of the diaphragm and slight independent movement of one valve element relatlvely to the other element, the flexibility of the diaphragm suflicing to take care of differences in expansion.

Formed in the shell of the valve element 2 is a port 6 serving to prevent the cell from becoming pressure-logged should there be a very slight leak through the diaphragm ]O1I1t.

In other respects the valve element 2 is closed on the side beyond the diaphragm 1, so that, in the event of fracture of the diaphragm, fragments thereof may be trapped in the cell. In screw-threaded engagement with that portion of the valve spindle 5 between the beats is a nut 8 adapted to be rotated until jammed against a sleeve-like extension 4 of the covering member 3, whereby both valve elements 2 and 7 will be seated simultaneously to permit grinding of the valve faces of both beats.

As will be evident the construction above described'may be substantially modified.

What we claim is 1. In a double beat valve, in combination with two valve elements, one element being formed with a port, a valve spindle between said elements, a covering member surrounding said spindle and affording in conjunction with said ported valve element a diaphragm cell, and a flexible diaphragm imprisoned in said cell and held between said covering'member and said ported valve element, said port arranged to admit pressure fluid to the back of the diaphragm.

2. In a double beat valve, in combination with two valve elements, a valve spindle between said elements, said spindle provided with screw threads, a covering member secured to one of said elements and formed with a sleeve-like extension surrounding said spindle and slidable thereon, said covering member affording in conjunction with the valve element to which it is secured a diaphragm cell a flexible diaphragm carried by said spindle, said diaphragm being imprisoned in said cell and held at its pcriphery between said covering member and names to this specification in the presence the last mentloned valve element, a backing of tWo subscrlbing Witnesses.

member secured to said spindle at the back DAVID COCKBURN. of said diaphragm and a nut threaded on DONALD MACNICOLL. 5 said spindle and adapted to be rotated into Witnesses:

jamming engagement With said extension. HENRY MASON,

In testimony whereof We have signed our FLORENCE HOUSTON.

Copies 0! this patent may be obtained or 'flve cents each, by addressing the "commissioner 0''! Patents.

Washington, D. 0." 

